Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Description of debt redemption features under terms of the debt agreement.

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Amount of cash inflow from issuance of long-term debt classified as other.

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DEBT Narrative 5 - Senior Notes (Details) - USD ($) $ in Thousands			12 Months Ended
	Sep. 14, 2020	May 22, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2021	Aug. 31, 2020	Apr. 15, 2018
Debt Instrument [Line Items]
Proceeds from note offerings, net of issuance costs	$ 1,182,000		$ 1,182,035	$ 491,580	$ 0
5.75% senior notes
Debt Instrument [Line Items]
Long-term debt	$ 600,000		$ 600,000	0
Long-term debt, rate	5.75%
Debt instrument, redemption, description			If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes, the 5.75% senior notes, the 6.0% senior notes, the 5.625% senior notes or the 6.375% senior notes, each holder of the applicable senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
6.375% senior notes
Debt Instrument [Line Items]
Long-term debt	$ 600,000		$ 600,000	0
Long-term debt, rate	6.375%
Debt instrument, redemption, description			If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes, the 5.75% senior notes, the 6.0% senior notes, the 5.625% senior notes or the 6.375% senior notes, each holder of the applicable senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
4.80% senior notes
Debt Instrument [Line Items]
Long-term debt			$ 0	450,000			$ 450,000
Long-term debt, rate							4.80%
6.00% senior notes
Debt Instrument [Line Items]
Long-term debt		$ 500,000	$ 500,000	500,000
Long-term debt, rate			6.00%
Proceeds from note offerings, net of issuance costs		$ 491,600
Debt instrument, redemption, description			If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes, the 5.75% senior notes, the 6.0% senior notes, the 5.625% senior notes or the 6.375% senior notes, each holder of the applicable senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
7.65% senior notes
Debt Instrument [Line Items]
Long-term debt								$ 350,000
Long-term debt, rate								7.65%
6.75% senior notes
Debt Instrument [Line Items]
Long-term debt			$ 300,000	300,000
Long-term debt, rate			6.75%
Debt instrument, redemption, description			If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes, the 5.75% senior notes, the 6.0% senior notes, the 5.625% senior notes or the 6.375% senior notes, each holder of the applicable senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.
6.75% senior notes \| Subsequent Event [Member]
Debt Instrument [Line Items]
Long-term debt						$ 300,000
Long-term debt, rate						6.75%
4.75% senior notes
Debt Instrument [Line Items]
Long-term debt			$ 250,000	250,000
Long-term debt, rate			4.75%
5.625% senior notes
Debt Instrument [Line Items]
Long-term debt			$ 550,000	$ 550,000
Long-term debt, rate			5.625%
Debt instrument, redemption, description			If we undergo a change of control, as defined in the supplemental indentures for the 6.75% senior notes, the 5.75% senior notes, the 6.0% senior notes, the 5.625% senior notes or the 6.375% senior notes, each holder of the applicable senior notes may require us to repurchase all or a portion of its notes at a price equal to 101% of the principal amount of the notes repurchased, plus any accrued and unpaid interest to the date of repurchase.